gcc4.0 recent >15% runtime performance regression
Uros Bizjak
uros@kss-loka.si
Mon Jan 3 07:32:00 GMT 2005
Hello!
>gcc-4.0-20050102
> 4010d4: movss (%ecx,%esi,4),%xmm0
> 4010d9: movss %xmm0,0x4(%esp)
> 4010df: movaps %xmm0,%xmm1
> 4010e2: movaps %xmm2,%xmm0
> 4010e5: flds (%edx,%ebx,4)
> 4010e8: mulss %xmm3,%xmm1
> 4010ec: movss (%edx,%esi,4),%xmm4
> 4010f1: fsubrs 0xc(%edi)
> 4010f4: mulss %xmm4,%xmm3
> 4010f8: movss (%edx,%eax,4),%xmm5
> 4010fd: movss (%ecx,%eax,4),%xmm7
> 401102: addss (%ecx,%ebx,4),%xmm1
> 401107: mulss %xmm5,%xmm2
> 40110b: mulss %xmm7,%xmm0
> 40110f: fstps (%esp)
> 401112: movss (%esp),%xmm6
> 401117: addss %xmm0,%xmm1
> 40111b: subss %xmm3,%xmm6
> 40111f: xorps %xmm3,%xmm3
>
Which -mfpmath= option did you use to produce above code?
Uros.
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